2082-79-3Relevant articles and documents
Synthesis of Fatty Alcohol based Sterically Hindered Esters as Potential Antioxidants for Bioadditives
Madhu, Devarapaga,Padmaja, Korlipara V.,Venkateshwarlu, Kontham
, p. 1309 - 1316 (2020/12/02)
Abstract: Four hindered phenolic esters were prepared by esterification between 3-(3,5-Di-tert-butyl-hydroxyphenyl)propionic acid and fatty alcohols. The synthesized esters were characterised by NMR, IR and ESI-MS and analysed for their antioxidant proper
Synthesis process of antioxidant 1076
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Paragraph 0012; 0050-0120; 0122, (2018/09/08)
The invention provides a method of organically synthesizing an antioxidant 1076, i.e. octadecyl 3-(3,5-ditert-butyl-4-hydroxyphenyl)propionate. The preparation method comprises the following steps: bytaking a mixed solution of ethylene glycol and methylbenzene as a solvent, and by taking methyl 3-(3,5-ditert-butyl-4-hydroxyphenyl)propionate and stearyl alcohol as reactants, adding a catalyst andreacting to obtain the octadecyl 3-(3,5-ditert-butyl-4-hydroxyphenyl)propionate. According to the preparation method, the mixed solution is used as the solvent, and the catalyst is added in batches ina reaction process, so that the organic synthesis method provided by the invention has the advantages that in the reaction of preparing the octadecyl 3-(3,5-ditert-butyl-4-hydroxyphenyl)propionate, the use amount of the catalyst is less, the reaction temperature is low, the obtained product is high in purity, and the yield is still up to 92 percent or above in pilot scale test.
Method for preparing n-Octadecyl-beta-(4-hydroxy-3,5-di-tert-butyl-phenyl)-propionate at high pressure
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Paragraph 0017-0028, (2017/02/17)
The invention relates to a method for preparing n-Octadecyl-beta-(4-hydroxy-3,5-di-tert-butyl-phenyl)-propionate at high pressure. The adopted technical scheme is that the method comprises the following steps of taking beta-(3,5-di-tert-butyl-4-hydroxyphenyl) methyl propionate, octadecanol, a catalyst and solvent, and enabling the substances to react at the pressure of 2 to 3MPa and the temperature of 110 to 120DEG C for 6 to 7 hours, thus obtaining the beta-(4-hydroxy-3,5-di-tert-butyl-phenyl)-propionate. The method disclosed by the invention is simple and is low in energy consumption, and wastes are utilized; the purity of the obtained n-Octadecyl-beta-(4-hydroxy-3,5-di-tert -butyl-phenyl)-propionate is high.
METHODS AND COMPOSITIONS FOR INHIBITING VINYL AROMATIC MONOMER POLYMERIZATION
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, (2013/03/26)
Methods and compositions are provided for inhibiting the polymerization of a vinyl aromatic monomer, such as styrene monomer, during elevated temperature processing thereof or during storage or shipment of polymer containing product. The compositions comprise a combination of a quinone methide derivative A) and a phenol compound B). The methods comprise adding from about 1-10,000 ppm of the combination to the monomer containing medium, per one million parts of the monomer.
Method for making hindered phenolic antioxidant
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Page/Page column 3-4, (2010/08/22)
A method for making a hindered phenolic antioxidant based on Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate uses a methanol solution containing alkali metal methoxide as a catalyst solution, wherein the catalyst solution is filtered with a filter device with a filter pore diameter of less than 50 μm to remove insoluble matters therefrom before used in a transesterification process where methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate and 1-Octadecanol are taken as reactants to obtain a crude product of Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate having high conversion rate and low color, and the crude product further undergoes a purification process for crystallization, filtering and drying to obtain a product of Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate having high purity and low color.
Nucleophilic acyl substitutions of esters with protic nucleophiles mediated by amphoteric, oxotitanium, and vanadyl species
Chen, Chien-Tien,Kuo, Jen-Huang,Ku, Cheng-Hsiu,Weng, Shiue-Shien,Liu, Cheng-Yuan
, p. 1328 - 1339 (2007/10/03)
(Chemical Equation Presented) A diverse array of oxometallic species were examined as catalysts in nucleophilic acyl substitution (NAS) reactions of methyl (or ethyl) esters with protic nucleophiles. Among them, oxotitanium acetylacetonate (TiO(acac)2) and vanadyl chloride (VOCl 2-(THF)x) served as the most efficient and water-tolerant catalysts. Transesterifications of methyl and/or ethyl esters with functionalized (including acid- or base-sensitive) 1° and 2° alcohols can be carried out chemoselectively in refluxed toluene or xylene in a 1:1 substrate stoichiometry using 1 mol % catalyst loading. The resultant products were furnished in 85-100% yields by simple aqueous workup to remove water-soluble catalysts. The new NAS protocol is also amenable to amines and thiols in 74-91% yields, albeit with higher loading (2.5 equiv) of protic nucleophiles. Representative examples of commercial interests such as Padimate O and antioxidant additives for plastics were also examined to demonstrate their practical applications. A 1:1 adduct between TiO(acac)2 and a given 1-octadecanol was identified as (C18H37O) 2Ti(acac)2 and was responsible for its subsequent NAS of methyl esters.
Mixture of substances containing compounds with vinyl groups and stabilizers
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, (2008/06/13)
A mixture contains one or more vinyl-containing compounds as component (A) and, as a further component, a stabilizer (B) which contains one or more readily volatile nitroxyl compounds as component (b1), one or more sparingly volatile nitroxyl compounds as component (b2), if required one or more aromatic nitro compounds as component (b3) and, if required, one or more iron compounds as component (b4).Stabilizers (B) contain the components (b1) and (b2), (b1) and (b2) and (b3), (b1) and (b2) and (b4), and (b1), (b2), (b3) and (b4), and the premature polymerization of vinyl-containing compounds during their purification or distillation is inhibited by a process in which a stabilizer (B) is added or the components of stabilizer (B) are added as individual substances or in at least two groups of the components.
Preparation of substituted hydroxyhydrocinnamate esters by continuous transesterification using reactive distillation
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, (2008/06/13)
Substituted hydroxyhydrocinnamate esters of the formula (I) where R is alkyl, n is 0 to 2, m is 1 to 4 and A is alkyl, interrupted or uninterrupted alkylene, alkanetriyl or pentaerythrityl, are prepared by continuous transesterification of the corresponding lower alkyl mono-ester with an alkanol or polyol of the formula A-(OH)m. This novel process comprises continuously introducing into and reacting the reactants in a heated distillation column reactor having a reaction zone which contains a solid, heterogeneous transesterification catalyst to form the compound of formula (I) and the corresponding lower alkanol; separating the products so formed based on their difference in volatility; and continuously removing said products from the distillation column at a steady rate, thereby preventing the reaction mixture from reaching chemical equilibrium. The continuous reaction results in improved product throughput and product quality and has a lower residence time, as compared to known batch-type processes.
Process for the preparation of substituted hydroxyhydrocinnamate esters
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, (2008/06/13)
The transesterification of substituted lower alkyl hydroxyhydrocinnamates with a higher alcohol or a polyol is greatly facilitated by the use of a trace amount of a tin catalyst. In many cases, the amount of the catalyst is so small that it is unnecessary to remove it from the final product by distillation of said product.
4-acylaminopiperidin-N-oxyle
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, (2008/06/13)
4-Acylaminopiperidine N-oxides Ia where A1 is hydrogen or an organic radical and B1 is a radical IIa STR1 where R1 -R4 are each C1 -C4 -alkyl and R1 and R2, on the one hand, and R3 and R4, on the other hand, may furthermore be bonded to form a 5-membered or 6-membered ring, R5 is H or C1 14 C4 -alkyl and R6 is H or C1 -C18 -alkyl, are used for stabilizing organic materials against the harmful effect of free radicals, particularly in the distillation of monomers which undergo free radical polymerization, especially styrene.